Wednesday, August 19, 2009

Debunking Cambrian Explosion Myths

I have heard creationists claim on multiple occasions that the Cambrian explosion disproves evolution. For example, Lee Strobel in this video claims that the all the phyla appeared at once, independently, and therefore they were created.

First we have to understand what the Cambrian explosion is. The Cambrian explosion occurred about 530 million years ago and lasted around 80 million years. (EDIT: Quasar brought to my attention that the exact length of time of the Cambrian explosion is under dispute. However, the lowest estimate is still around 5 million years.) During this time, many of the phyla or general body types first appeared for animals. Before the Cambrian explosion, very few fossils exist of multicellular creatures, and life appears to be mainly composed of single cell organisms.

However, not all phyla made their appearance during the Cambrian explosion. Land-based life such as flowers, ferns, etc... developed much later.

While fossils from the Cambrian explosion and Precambrian are rare, evidence exists that all these body types did not evolve completely independently. All animal phyla, for example, share many common characteristics. They are all triploblastic (the embryo forms in 3 layers), bilatteral (have left and right halves) coelomates (have internal body organs). Therefore, evidence of common ancestry is suggested in the formation of these early phyla groups.

More importantly, geologists found fossils predating the Cambrian explosion of burrows which require a digging mechanism and multicellular creatures. So the idea that creatures found in the Cambrian explosion arose without precedent is simply untrue. Life had been developing into more complex, multicellular forms in the Precambrian.

The easiest way to explain the Cambrian explosion is through the theory of punctuated equilibrium. According to the theory, the evolution of most sexually-reproducing creatures occurs in short bursts followed by long stretches of few changes.

While the theory of punctuated equilibrium may have been over-sold, the idea that changes to the environment spur evolutionary development is well understood by biologists. After all, the information for evolution comes from the environment - change the environment, change the creature.

It just so happens that the amount of oxygen in Earth's atmosphere dramatically rose during the time of the Cambrian explosion, giving animals more oxygen to work with. This extra oxygen could have enabled creatures to grow larger than ever before without suffocating their body parts due to a lack of oxygen.

So while much remains to be learned about the Cambrian explosion, the idea that it somehow proves that omnipotent deity magically created life on Earth is a very much unwarranted.

12 comments:

  1. As one person put it on richarddawkins.net, the cambrian appears to be the start of the crunchyness arms race. soft -> crunchy. shells, teeth, claws, etc...

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  2. Also, those hard pieces make for better fossils. :)

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  3. However, it certainly doesn't take magic to create!Obviously the remarkable complexity of the world around us SCREAMS, "CREATOR". Consider that almost every technological development invented by we "creatures" have been derived from nature. Nothing magical about that.Pure intelligence.

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  4. I don't see any debunking here.

    I see a lot of poorly researched conclusions, e.g.:
    ''They are all triploblastic (the embryo forms in 3 layers), bilatteral (have left and right halves) coelomates (have internal body organs). Therefore, evidence of common ancestry is suggested in the formation of these early phyla groups.''

    'Suggested'? Now come on. The similarity proves only fitness to the environment. It could equally prove that there was a maker. The fact is that the Cambrian Explosion 'suggests', objectively, that there is a problem with evolutionary theory. You can't get away with another subjective 'suggestion' and claim you've debunked creationism. You've made no account of the sheer variety of life, nor have you shown any objective studies of how this could have been caused by a sudden increase in oxygen (technically a aging poison).

    ''So while much remains to be learned about the Cambrian explosion, the idea that it somehow proves that omnipotent deity magically created life on Earth is a very much unwarranted''

    Yet you have proved nothing of the sort!

    Come on. That is weak. You can do better than that, surely?

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  5. So you do not agree with the evidence provided for you eh wargamessociety? Then what would you provide to back your claims and remember abra cadabra does not cut it. However, if you believe your made up god did it, then simply provide evidence for your god, define the god who did it, and provide the explanation of what created your god. If all complex things need a creator and your god is complex, then what made magic man in space? The science is solid and even if you don't like it, genetic code is surely even more solid. Forgive me if this is to much for you understand, I know how easy it is to just let someone else do the thinking for you. However Kitmiller v Dover already put those thoughts to rest and they went to creationist hell only to be come back from the dead as ID lol. Read a book and talk to the pros and stop listening to banana and Mr. crockaduck. You silly primate/monkey/ape!

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  6. The fact that you use ad hominem points to your own uncertainties. God is transcendental by definition, as he created the matter and energy in our universe. IF you had a rudimentary understanding of physics you could see the underlying beauty of the rules that govern the cosmos.

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  7. the omnimegauniverse is transcendental by definition and made god.

    See how easy it is to just define things without evidence!

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  8. the fact that there was an explosions of complex creatures in a short time. The time periods for other creatures is being expanding and may are being pushed back in time towards the Cambrian period. So if all the creatures are coming closer together and there is a sudden explosion of them with little before it what does that suggest. Especially when they keep saying there was a sudden explosion of creatures then a sudden extinction. This is another way of saying the animals appeared suddenly with no traces before and after. That to me suggests a creator.

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  9. Creation would certainly better explain the events of this era than evolution. Even with sudden changes like an increase in available oxygen, there is a question of whether living things could evolve changes so quickly, given the fact that most mutations are failures, and even a mutation that improves the species must be successfully passed on (and the individual lives longenoughto past it on). Science cannot prove a creator but also cannot prove evolution. The debate continues.

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  10. this is for Patrick but everyone can benefit from it. The beings name whom created the universe and everything in it is called Yahweh. He lives in a dimension in which humans can not go to. That is why we, humans don't, won't understand how he created. The way we calculate time is not correct because we base science on theory based on trial and error. We see physical and natural events which we base our conclusions on. The problem with that is that we do not know what lies outside the dimensions we encounter. Because we are limited with knowledge, we can not see passed what we consider as reality. evolution is not an exact science, too many holes. Not enough transitional species and if we use that just we ourselves can not explain our existence. If we evolved from apes, monkeys why hasn't the former died out? geologist now have proven that the way we tell time from objects is and has been incorrect. There is to much information now that gives cause to reconsider what we thought was truth in science. We must weigh how we base our conclusions by what we consider truth is, and when error is ignored.

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